Techniques for percutaneous mitral valve replacement and sealing

ABSTRACT

Apparatus and methods are described, including one or more valve support guide members that are delivered to one or more commissures of a native atrioventricular valve of a patient. A prosthetic valve support is advanced toward the native valve along the one or more valve support guide members and placed at the native valve. A prosthetic valve is coupled to the valve support. One or more sealing elements facilitate sealing of an interface between the prosthetic valve support and the native valve. Other applications are also described.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application is a continuation-in-part of U.S. Ser. No.12/840,463 to Hacohen, filed Jul. 21, 2010, entitled “Guide wires withcommissural anchors to advance a prosthetic valve,” which published asUS 2012/0022639, and which is incorporated herein by reference.

FIELD OF THE INVENTION

Embodiments of the present invention relate in general to valvereplacement. More specifically, embodiments of the present inventionrelate to prosthetic valves for replacement of an atrioventricularvalve.

BACKGROUND

Ischemic heart disease causes regurgitation of a heart valve by thecombination of ischemic dysfunction of the papillary muscles, and thedilatation of the ventricle that is present in ischemic heart disease,with the subsequent displacement of the papillary muscles and thedilatation of the valve annulus.

Dilation of the annulus of the valve prevents the valve leaflets fromfully coapting when the valve is closed. Regurgitation of blood from theventricle into the atrium results in increased total stroke volume anddecreased cardiac output, and ultimate weakening of the ventriclesecondary to a volume overload and a pressure overload of the atrium.

SUMMARY

For some applications of the present invention, one or more guidemembers (e.g., wires, sutures, or strings) is configured to be anchoredto respective commissures of a native atrioventricular valve of apatient, and each guide member facilitates the advancement therealong ofrespective commissural anchors. The commissural anchors are shaped so asto define a plurality of barbs or prongs which are expandable torestrict proximal movement of the anchors following their deployment.The guide members facilitate advancement of a collapsible prostheticvalve support (e.g., a skirt) which serves as a base for and receives acollapsible prosthetic mitral valve which is subsequently coupled to thesupport. The support comprises a proximal annular element, or ring, anda distal cylindrical element. The cylindrical element is configured topush aside and press against the native leaflets of the native valve,and the proximal annular element is shaped so as to define one or moreholes for sliding the valve support along the one or more guide members.The proximal annular element is configured to be positioned along theannulus of the native valve.

The collapsible prosthetic valve is configured for implantation inand/or at least partial replacement (e.g., full replacement) of thenative atrioventricular valve of the patient, such as a native mitralvalve or a native tricuspid valve. The valve support and the prostheticvalve are configured to assume collapsed states for minimally-invasivedelivery to the diseased native valve, such as by percutaneous ortransluminal delivery using one or more catheters. For someapplications, the valve support and the prosthetic valve are implantedduring an open-heart procedure.

The prosthetic valve support is shaped so as to define a downstreamskirt. The downstream skirt is configured to be placed at native valve,such that the downstream skirt passes through the orifice of the nativevalve and extends toward, and, typically partially into, a ventricle.The downstream skirt typically additionally pushes aside and pressesagainst the native leaflets of the native valve, which are left in placeduring and after implantation of the prosthetic valve support and/or theprosthetic valve.

The proximal annular element has upper and lower surfaces. For someapplications of the present invention, one or more, e.g., a pluralityof, tissue anchors are coupled to the lower surface and facilitateanchoring of the proximal annular element to the annulus of the nativevalve. For some applications, the one or more anchors comprise at leastfirst and second commissural anchors that are configured to be implantedat or in the vicinity of the commissures of the native valve.

The cylindrical element of the valve support has first and second endsand a cylindrical body disposed between the first and second ends. Thefirst end of the cylindrical element is coupled to the annular elementwhile the second end defines a free end of the cylindrical element. Forsome applications of the present invention, the cylindrical element ofthe valve support is invertible such that (1) during a first period, thesecond end and the cylindrical body of the cylindrical element aredisposed above the annular element (e.g., in the atrium of the heart),and (2) during a second period, the second end and the cylindrical bodyof the cylindrical element are disposed below the annular element (e.g.,in the ventricle of the heart).

For some applications, techniques are applied to facilitate sealing ofthe interface between the valve support and the native valve, and/or theinterface between the prosthetic valve and the native valve. Forexample, a sealing balloon may be placed on a valve-facing, lower sideof the annular element of the valve support, the sealing balloon beingconfigured to be inflated such that the balloon seals the interfacebetween the valve support and the native valve. Alternatively oradditionally, commissural helices are wrapped around chordae tendineaeof the patient in order to facilitate sealing of the valve commissuresaround the valve support and/or around the valve. Further alternativelyor additionally, the valve commissures are grasped by grasping elementsthat act in order to facilitate sealing of the commissures around thevalve support and/or around the valve. For some applications, one ormore of the aforementioned sealing elements facilitates anchoring of theprosthetic valve to the native valve in addition to facilitatingsealing.

For some applications, the prosthetic valve comprises a wire frame, anda sealing material (such as latex) is disposed on the outer surface ofthe wire frame so as to form webbing between at least some of the strutsof the wire frame, and to provide sealing between the wire frame and thenative valve.

For some applications, an invertible prosthetic valve support is used tosupport a prosthetic valve. Typically, a sealing element is disposedcircumferentially around a surface of the invertible prosthetic valvesupport that is initially an inner surface of the invertible prostheticvalve support. The invertible prosthetic valve support is anchored tothe native valve, and is subsequently inverted. Subsequent to theinversion of the invertible prosthetic valve support, the sealingelement is disposed on the outer surface of the invertible prostheticvalve support and acts to seal the interface between the outer surfaceand the native valve.

There is therefore provided, in accordance with some applications of thepresent invention, apparatus, including:

one or more valve support guide members configured to be delivered toone or more commissures of a native atrioventricular valve of a patient;

a prosthetic valve support configured to be advanced toward the nativevalve along the one or more valve support guide members and placed atthe native valve;

a prosthetic valve configured to be coupled to the valve support; and

one or more sealing elements configured to facilitate sealing of aninterface between the prosthetic valve support and the native valve.

For some applications, the sealing element includes a balloon disposedcircumferentially around an outer surface of the prosthetic valvesupport.

For some applications, the sealing element includes one or more helicesthat are configured to facilitate sealing of commissures of the nativevalve with respect to the valve support by being wrapped around chordaetendineae of the native valve.

For some applications, the sealing element includes grasping elementsthat are configured to facilitate sealing of commissures of the nativevalve with respect to the valve support by grasping the commissures.

For some applications, the sealing element is configured to facilitateanchoring of the support to the native valve.

For some applications, the valve support is collapsible fortranscatheter delivery and expandable to contact the nativeatrioventricular valve.

For some applications, the prosthetic valve includes two or moreprosthetic leaflets.

For some applications, the native atrioventricular valve includes amitral valve, and the prosthetic valve includes three prostheticleaflets.

For some applications, the valve support guide members are removablefrom the patient following coupling of the prosthetic valve to the valvesupport.

For some applications, the valve support is shaped so as to define adistal portion which is configured to push aside, at least in part,native leaflets of the valve of the patient.

For some applications, the valve support is shaped so as to define oneor more holes, the one or more holes being configured to facilitateslidable passage therethrough of a respective one of the one or morevalve support guide members.

For some applications, the one or more valve support guide membersincludes one valve support guide member that is looped through first andsecond commissures of the atrioventricular valve in a manner in which alooped portion of the valve support guide member is disposed in aventricle of the patient and first and second free ends of the valvesupport guide member are accessible from a site outside a body of thepatient.

For some applications, the apparatus further includes:

a guide wire configured to be advanced, via the native atrioventricularvalve, into a ventricle of the patient, and coupled to an inner wall ofthe patient's ventricle; and

a valve support guide member tube coupled to the guide wire,

and a distal portion of the valve support guide member is configured toloop through the valve support guide member tube, such that, in responseto the valve support guide member being pushed distally, portions of thevalve support guide member are pushed to respective commissures of thenative valve.

For some applications, the prosthetic valve is shaped so as to defineone or more protrusions configured to ensnare one or more nativeleaflets of the native valve of the patient.

For some applications, the protrusions are disposed in a sinusoidalconfiguration such that the protrusions conform with a saddle shape ofthe patient's native annulus.

For some applications, the protrusions are configured to prevent thenative leaflets from interfering with a left ventricular outflow tractof the patient, by sandwiching the leaflets between the protrusions andthe prosthetic valve support.

For some applications, the valve support includes:

a first end that is configured to be placed on an atrial side of anative atrioventricular valve of a patient; and

a second end that is configured, during a first period, to be disposedinside the patient's atrium, above the first end of the valve support,

the valve support being at least partially invertible in a manner inwhich, during a second period, the second end of the valve support isdisposed at least partially inside a ventricle of the patient, below thefirst end of the valve support.

For some applications, the valve support includes an annular element anda generally cylindrical element coupled to the annular element, thegenerally cylindrical element being configured to push aside nativeleaflets of the native valve, and the cylindrical element has first andsecond ends and a cylindrical body that is disposed between the firstand second ends.

For some applications, the sealing element includes a balloon disposedunderneath the annular element and configured to facilitate sealing ofan interface between the annular element and the native valve.

For some applications, the apparatus further includes one or moreprosthetic valve guide members, the prosthetic valve guide members beingconfigured to facilitate advancement of the prosthetic valve therealongand toward the valve support.

For some applications:

the first end of the cylindrical element is coupled to the annularelement,

during a first period, the second end of the cylindrical element isdisposed above the annular element in a manner in which the body of thecylindrical element is disposed above the annular element, and

the cylindrical element is invertible in a manner in which, during asecond period, the second end of the cylindrical element is disposedbelow the annular element and the body of the cylindrical element isdisposed below the annular element.

For some applications:

during the first period, the second end of the cylindrical element isdisposed in an atrium of a heart of the patient and the annular elementis positioned along an annulus of the native valve,

the prosthetic valve is advanceable along the one or more prostheticvalve guide members into a ventricle of the heart of the patient, and

in response to advancement of the prosthetic valve into the ventricle,the one or more prosthetic valve guide members are pulled into theventricle and pull the second end and the body of the cylindricalelement into the ventricle to invert the cylindrical element.

There is further provided, in accordance with some applications of thepresent invention, apparatus, including:

a prosthetic valve support configured to be advanced toward a nativeatrioventricular valve of a patient and placed at the native valve;

a prosthetic valve configured to be coupled to the valve support, theprosthetic valve being shaped so as to define first and second sets ofone or more protrusions, each set of protrusions configured to ensnare arespective native leaflet of the native valve of the patient, the firstset of protrusions being disposed within a first circumferential arcwith respect to a longitudinal axis of the prosthetic valve, on a firstside of a distal end of the prosthetic valve, the second set ofprotrusions being disposed within a second circumferential arc withrespect to the longitudinal axis of the prosthetic valve, on a secondside of the distal end of the prosthetic valve, the first and secondsets being disposed so as to provide first and second gaps therebetweenat the distal end of the prosthetic valve, at least one of the gapshaving a circumferential arc of at least 20 degrees; and

one or more valve guide members configured to be delivered to one ormore commissures of the native valve, and to guide the valve such thatthe first and second circumferential arcs are aligned with respectiveleaflets of the native valve and such that the first and second gaps arealigned with respective commissures of the native valve.

For some applications, the at least one of the gaps has acircumferential arc of at least 60 degrees.

For some applications, the first circumferential arc defines an angle ofbetween 25 degrees and 90 degrees about the longitudinal axis of theprosthetic valve.

For some applications, the second circumferential arc defines an angleof between 25 degrees and 90 degrees about the longitudinal axis of theprosthetic valve.

For some applications, the first circumferential arc defines an angle ofbetween 45 degrees and 75 degrees about the longitudinal axis of theprosthetic valve.

For some applications, the second circumferential arc defines an angleof between 45 degrees and 75 degrees about the longitudinal axis of theprosthetic valve.

There is additionally provided, in accordance with some applications ofthe present invention, a method, including:

determining an area defined by an annulus of a native atrioventricularvalve of a patient;

selecting a prosthetic valve to be placed in the native valve bydetermining that the valve defines a cross-sectional area that is lessthan 90% of the area defined by the annulus; and

deploying the prosthetic valve at the native valve,

the selecting of the prosthetic valve facilitating sealing of the nativevalve with respect to the prosthetic valve by facilitating closing ofleaflets of the native valve around the prosthetic valve, upondeployment of the prosthetic valve.

For some applications, selecting the prosthetic valve includes selectinga prosthetic valve having a material disposed on an outer surfacethereof.

For some applications, selecting the prosthetic valve includes selectinga prosthetic valve having a material that prevents tissue growthdisposed on an outer surface thereof.

For some applications, selecting the prosthetic valve includes selectinga prosthetic valve having a material that promotes tissue growthdisposed on an outer surface thereof.

For some applications, selecting the prosthetic valve to be placed inthe native valve includes determining that the valve defines across-sectional area that is less than 80% of the area defined by theannulus.

For some applications, selecting the prosthetic valve to be placed inthe native valve includes determining that the valve defines across-sectional area that is less than 60% of the area defined by theannulus.

There is further provided, in accordance with some applications of thepresent invention, apparatus including:

a valve support for receiving a prosthetic valve, the valve supportincluding:

-   -   a first end that is configured to be placed on an atrial side of        a native atrioventricular valve of a patient; and    -   a second end that is configured, during a first period, to be        disposed inside the patient's atrium, above the first end of the        valve support,    -   the valve support being at least partially invertible in a        manner in which, during a second period, the second end of the        cylindrical element is disposed at least partially inside a        ventricle of the patient, below the first end of the valve        support.

For some applications, the valve support includes a flexible wireframecovered by a fabric.

For some applications, the valve support is collapsible fortranscatheter delivery and expandable to contact the nativeatrioventricular valve.

For some applications, the valve support defines a surface that is aninner surface of the valve support during the first period, and an outersurface of the valve support during the second period, and the apparatusfurther includes a sealing material that is disposed on the surface,such that during the second period the sealing material facilitatessealing between the valve support and the native valve.

For some applications, the first end includes a coupling elementconfigured to couple the valve support to tissue of the native valve onthe atrial side of the native valve.

For some applications, the first end is shaped to define barbs that areconfigured to couple the valve support to tissue of the native valve onthe atrial side of the native valve

For some applications, the valve support includes:

an annular element configured to be positioned along a native annulus ofthe native atrioventricular valve; and

a flexible generally cylindrical element configured to be positioned inthe native atrioventricular valve of the patient and to push asidenative leaflets of the native valve, the first end of the cylindricalelement defining the first end of the valve support, and the first endof the cylindrical element being coupled to the annular element.

For some applications, the apparatus further includes one or more valvesupport guide members configured to be delivered to one or morecommissures of the native atrioventricular valve of the patient, and theone or more valve support guide members are configured to facilitateadvancement of the valve support toward the native valve.

For some applications, the valve support is shaped so as to define oneor more holes, the one or more holes configured to facilitate slidablepassage therethrough of a respective one of the one or more valvesupport guide members.

For some applications, the one or more valve support guide membersincludes one valve support guide member that is looped through first andsecond commissures of the atrioventricular valve in a manner in which alooped portion of the valve support guide member is disposed in aventricle of the patient and first and second free ends of the valvesupport guide member are accessible from a site outside a body of thepatient.

For some applications, the apparatus further includes:

a guide wire configured to be advanced, via the native atrioventricularvalve, into a ventricle of the patient, and coupled to an inner wall ofthe patient's ventricle; and

a valve support guide member tube coupled to the guide wire,

and a distal portion of the valve support guide member is configured toloop through the valve support guide member tube, such that, in responseto the valve support guide member being pushed distally, portions of thevalve support guide member are pushed to respective commissures of thenative valve.

For some applications, the apparatus further includes one or moreprosthetic valve guide members reversibly couplable to the cylindricalelement in a vicinity of the second end of the cylindrical element, theprosthetic valve guide members being configured to facilitateadvancement of the prosthetic valve therealong and toward the valvesupport.

For some applications, the apparatus further includes the prostheticvalve, and the prosthetic valve is couplable to the valve support.

For some applications:

during the first period, the second end of the cylindrical element isdisposed in an atrium of a heart of the patient and the annular elementis positioned along an annulus of the native valve,

the prosthetic valve is advanceable along the one or more prostheticvalve guide members into a ventricle of the heart of the patient, and

in response to advancement of the prosthetic valve into the ventricle,the one or more prosthetic valve guide members are pulled into theventricle and pull the second end of the cylindrical element into theventricle to invert the cylindrical element.

For some applications, the apparatus further includes one or moresealing elements configured to facilitate sealing of an interfacebetween the prosthetic valve support and the native valve.

For some applications, the sealing element includes a balloon disposedcircumferentially around a surface of the prosthetic valve support.

For some applications, the sealing element includes one or more helicesthat are configured to facilitate sealing of commissures of the nativevalve with respect to the valve support by being wrapped around chordaetendineae of the native valve.

For some applications, the sealing element includes grasping elementsthat are configured to facilitate sealing of commissures of the nativevalve with respect to the valve support by grasping the commissures.

For some applications, the sealing element is configured to facilitateanchoring of the support to the native valve.

For some applications, the apparatus further includes the prostheticvalve, and the prosthetic valve is couplable to the valve support.

For some applications, the prosthetic valve is collapsible fortranscatheter delivery and expandable when exposed from within adelivery catheter.

For some applications, the prosthetic valve includes two or moreprosthetic leaflets.

For some applications, the native atrioventricular valve includes amitral valve, and the prosthetic valve includes three prostheticleaflets.

For some applications, the prosthetic valve is shaped so as to defineone or more protrusions configured to ensnare one or more nativeleaflets of the native valve of the patient.

For some applications, the protrusions are disposed in a sinusoidalconfiguration such that the protrusions conform with a saddle shape ofthe patient's native annulus.

For some applications, the protrusions are configured to prevent thenative leaflets from interfering with a left ventricular outflow tractof the patient, by sandwiching the leaflets between the protrusions andthe prosthetic valve support.

There is further provided, in accordance with some applications of thepresent invention, apparatus, including:

a guide wire configured to be advanced into a patient's ventricle via anative atrioventricular valve of the patient, and coupled to an innerwall of the patient's ventricle;

a valve support guide member tube coupled to the guide wire;

a valve support guide member, a distal portion of the valve supportguide member looping through the valve support guide member tube, suchthat, in response to the valve support guide member being pusheddistally, portions of the valve support guide member are pushed torespective commissures of the native valve;

a prosthetic valve support configured to be advanced toward thecommissures of the native valve along the valve support guide memberportions; and

a prosthetic valve configured to be coupled to the valve support.

For some applications, first and second free ends of the valve supportguide member are accessible from a site outside a body of the patient.

For some applications, the valve support includes:

an annular element configured to be positioned along a native annulus ofthe native atrioventricular valve; and

a generally cylindrical element configured to be positioned in thenative atrioventricular valve of the patient and to push aside nativeleaflets of the native valve, the cylindrical element being coupled tothe annular element, at a first end of the cylindrical element.

For some applications, the valve support is shaped so as to define oneor more holes, the one or more holes configured to facilitate slidablepassage therethrough of respective portions of the portions of the valvesupport guide member.

For some applications, the guide member is configured to facilitateadvancement of the prosthetic valve therealong and toward the valvesupport.

For some applications, the prosthetic valve is collapsible fortranscatheter delivery and expandable when exposed from within adelivery catheter.

For some applications, the prosthetic valve includes two or moreprosthetic leaflets.

For some applications, the native atrioventricular valve includes amitral valve, and the prosthetic valve includes three prostheticleaflets.

For some applications, the guide member is removable from the patientfollowing the coupling of the prosthetic valve to the valve support.

For some applications, the prosthetic valve is shaped so as to defineone or more protrusions configured to ensnare one or more nativeleaflets of the native valve of the patient.

For some applications, the protrusions are disposed in a sinusoidalconfiguration such that the protrusions conform with a saddle shape ofthe patient's native annulus.

For some applications, the protrusions are configured to prevent thenative leaflets from interfering with a left ventricular outflow tractof the patient, by sandwiching the leaflets between the protrusions andthe prosthetic valve support.

For some applications, the apparatus further includes one or moresealing elements configured to facilitate sealing of an interfacebetween the prosthetic valve support and the native valve.

For some applications, the sealing element includes a balloon disposedcircumferentially around a surface of the prosthetic valve support.

For some applications, the sealing element includes one or more helicesthat are configured to facilitate sealing of commissures of the nativevalve with respect to the valve support by being wrapped around chordaetendineae of the native valve.

For some applications, the sealing element includes grasping elementsthat are configured to facilitate sealing of commissures of the nativevalve with respect to the valve support by grasping the commissures.

For some applications, the sealing element is configured to facilitateanchoring of the support to the native valve.

There is additionally provided, in accordance with some applications ofthe present invention, apparatus, including:

one or more valve guide members configured to be delivered to one ormore commissures of a native atrioventricular valve of a patient;

a prosthetic valve configured to be advanced to be advanced toward thenative valve along the one or more valve guide members and placed at thenative valve at least the one or more commissures; and

one or more proximally-facing grasping elements that are configured tofacilitate sealing of commissures of the native valve with respect tothe valve by:

-   -   being inserted into a ventricle of the patient; and    -   being pulled proximally and being closed around tissue in a        vicinity of the commissures.

For some applications, the grasping elements include two surfaces thatare hingedly coupled to one another, and that are configured tofacilitate the sealing of the commissures of the native valve withrespect to the prosthetic valve by being closed about the hinge withrespect to one another.

There is further provided, in accordance with some applications of thepresent invention, a method, including:

advancing one or more valve support guide members toward one or morecommissures of a native atrioventricular valve of a patient;

placing a prosthetic valve support at the native atrioventricular valveby advancing the valve support along the one or more valve support guidemembers;

coupling a prosthetic valve to the prosthetic valve support; and

facilitating sealing of an interface between the prosthetic valvesupport and the native valve by deploying a sealing element in avicinity of the interface.

There is additionally provided, in accordance with some applications ofthe present invention, a method including:

placing a first end of a prosthetic valve support on an atrial side of anative atrioventricular valve of a patient, such that a second end ofthe valve support is disposed, during a first period, inside thepatient's atrium, above the first end of the valve support; and

subsequent to the placing of the valve support, inverting at least aportion of the valve support such that, during a second period, thesecond end of the valve support is disposed at least partially inside aventricle of the patient, below the first end of the valve support.

There is additionally provided, in accordance with some applications ofthe present invention, a method, including:

advancing a guide wire, via a native atrioventricular valve, into aventricle of the patient, a valve support guide member tube beingcoupled to the guide wire;

coupling a distal end of the guide wire to an inner wall of thepatient's ventricle; and

causing portions of a valve support guide member to be pushed torespective commissures of the native valve, by pushing the guide memberdistally, a distal portion of the valve support guide member loopingthrough the valve support guide member tube;

advancing a prosthetic valve support toward the commissures of thenative valve along the valve support guide member portions; and

coupling a prosthetic valve to the valve support.

There is further provided, in accordance with some applications of thepresent invention, a method, including:

advancing one or more valve guide members toward one or more commissuresof a native atrioventricular valve of a patient;

placing a prosthetic valve at the native atrioventricular valve byadvancing the valve along the one or more valve guide members; and

facilitating sealing of commissures of the native valve with respect tothe valve by:

-   -   inserting into a ventricle of the patient one or more grasping        elements that are coupled to the prosthetic valve;    -   pulling the grasping elements proximally; and    -   closing the grasping elements around tissue in a vicinity of the        commissures.

The present invention will be more fully understood from the followingdetailed description of embodiments thereof, taken together with thedrawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-B are schematic illustrations of advancement of one or moreguide members toward respective commissures of a mitral valve, inaccordance with some applications of the present invention;

FIGS. 1C-D are schematic illustrations of the advancement and deploymentof commissural anchors via the guide members, in accordance with someapplications of the present invention;

FIGS. 2A-D are schematic illustrations of the advancement of aprosthetic valve support toward a native atrioventricular valve of apatient, in accordance with some applications of the present invention;

FIGS. 2E-F are schematic illustrations of locking of the prostheticvalve support at the native valve, in accordance with some applicationsof the present invention;

FIGS. 2G-K are schematic illustrations of the advancement of aprosthetic valve and the coupling of the prosthetic valve to the valvesupport, in accordance with some applications of the present invention;

FIGS. 3A-B are schematic illustrations of the advancement of aprosthetic valve support toward a native atrioventricular valve of apatient, the valve support including a sealing balloon, in accordancewith some applications of the present invention;

FIGS. 3C-D are schematic illustrations of locking of the prostheticvalve support at the native valve, the valve support including thesealing balloon, in accordance with some applications of the presentinvention;

FIGS. 4A-C are schematic illustrations of a valve support being usedwith commissural helices that facilitate anchoring and/or sealing of thevalve support, in accordance with some applications of the presentinvention;

FIGS. 5A-D are schematic illustrations of grasping elements being usedto anchor and/or provide sealing of a prosthetic valve, in accordancewith some applications of the present invention;

FIGS. 6A-B are schematic illustrations of a prosthetic valve thatincludes a sealing material, in accordance with some applications of thepresent invention;

FIGS. 7A-F are schematic illustrations of a guide wire delivery system,in accordance with some applications of the present invention;

FIGS. 8A-C are schematic illustrations of a valve support that has acylindrical element that is invertible, in accordance with someapplications of the present invention;

FIGS. 9A-D are schematic illustrations of the advancement of aninvertible prosthetic valve support toward a native atrioventricularvalve of a patient, in accordance with some applications of the presentinvention;

FIG. 9E is a schematic illustration of inversion of the invertibleprosthetic valve support at the native valve, in accordance with someapplications of the present invention;

FIGS. 9F-H are schematic illustrations of the advancement of aprosthetic valve and the coupling of the prosthetic valve to theinvertible valve support, in accordance with some applications of thepresent invention;

FIG. 10 is a schematic illustration of a prosthetic valve, thecross-sectional area of which is smaller than the area defined by thepatient's native valve annulus, in accordance with some applications ofthe present invention;

FIGS. 11A-D are schematic illustrations of a prosthetic valve thatdefines protrusions from portions of the distal end of the valve, inaccordance with some applications of the present invention; and

FIGS. 12A-C are schematic illustrations of a prosthetic valve thatdefines distal protrusions that are disposed sinusoidally around thecircumference of the valve, in accordance with some applications of thepresent invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference is now made to FIGS. 1A-B, which are schematic illustrationsof a system 20 for replacing an atrioventricular valve 5 of a patientcomprising one or more guide members 21 a and 21 b which are advancedtoward first and second commissures 8 and 10 of valve 5 of a heart 2 ofthe patient, in accordance with some applications of the presentinvention. For some applications, guide members 21 a and 21 b comprisedistinct guide members. Alternatively (as shown in FIGS. 8A-F), only oneguide member is looped through commissures 8 and 10 in a manner in whichthe guide member defines a looped portion between commissures 8 and 10(i.e., a portion of the guide member that is disposed in a ventricle 6of heart 2), and first and second free ends which are disposed andaccessible at a site outside the body of the patient. For suchapplications, the guide member defines portions 21 a and 21 b.

For some applications, guide members 21 a and 21 b comprise guide wireshaving a diameter of 0.035 inches.

The transcatheter procedure typically begins with the advancing of asemi-rigid guide wire into a right atrium 4 of the patient. Thesemi-rigid guide wire provides a guide for the subsequent advancement ofa sheath 25 therealong and into the right atrium. Once sheath 25 hasentered the right atrium, the semi-rigid guide wire is retracted fromthe patient's body. Sheath 25 typically comprises a 13-20 F sheath,although the size may be selected as appropriate for a given patient.Sheath 25 is advanced through vasculature into the right atrium using asuitable point of origin typically determined for a given patient. Forexample:

-   -   sheath 25 may be introduced into the femoral vein of the        patient, through an inferior vena cava, into the right atrium,        and into the left atrium transseptally, typically through the        fossa ovalis;    -   sheath 25 may be introduced into the basilic vein, through the        subclavian vein to the superior vena cava, into the right        atrium, and into the left atrium transseptally, typically        through the fossa ovalis; or    -   sheath 25 may be introduced into the external jugular vein,        through the subclavian vein to the superior vena cava, into the        right atrium, and into the left atrium transseptally, typically        through the fossa ovalis.

In some applications of the present invention, sheath is advancedthrough the inferior vena cava of the patient and into the right atriumusing a suitable point of origin typically determined for a givenpatient.

Sheath 25 is advanced distally until sheath 25 reaches the interatrialseptum. For some applications, a resilient needle and a dilator (notshown) are advanced through the sheath and into the heart. In order toadvance the sheath transseptally into the left atrium, the dilator isadvanced to the septum, and the needle is pushed from within the dilatorand is allowed to puncture the septum to create an opening thatfacilitates passage of the dilator and subsequently the sheaththerethrough and into the left atrium. The dilator is passed through thehole in the septum created by the needle. Typically, the dilator isshaped to define a hollow shaft for passage along the needle, and thehollow shaft is shaped to define a tapered distal end. This tapereddistal end is first advanced through the hole created by the needle. Thehole is enlarged when the gradually increasing diameter of the distalend of the dilator is pushed through the hole in the septum.

The advancement of sheath 25 through the septum and into the left atriumis followed by the extraction of the dilator and the needle from withinsheath 25.

FIGS. 1C-D and 2A-B show advancement of one or more tissue anchors 30 aand 30 b along guide members 21 a and 21 b, respectively. Anchors 30 aand 30 b comprise a flexible, biocompatible material (e.g., nitinol) andcomprise one or more (e.g., a plurality of) radially-expandable prongs32 (e.g., barbs). Each anchor 30 a and 30 b is reversibly coupled to arespective delivery lumen 27 a and 27 b. Each delivery lumen 27 slidesaround a respective guide member 21. A respective surrounding sheath 26a and 26 b surrounds each delivery lumen 27 a and 27 b and aroundanchors 30 a and 30 b at least in part in order to compress and preventexpansion of prongs 32 of tissue anchors 30 a and 30 b.

As shown in FIG. 1D, the distal ends of lumens 27 a and 27 b arereversibly coupled to ribbed crimping structures 34. As describedhereinbelow, anchors 30 a and 30 b are anchored to ventricular surfacesof commissures 8 and 10. Following the anchoring, ribbed crimpingstructures 34 extend from anchors 30 a and 30 b through commissures 8and 10, respectively, and toward the atrial surfaces of commissures 8and 10. Ribbed crimping structures 34 are configured to facilitateanchoring of a valve support (described hereinbelow) to the atrialsurfaces of commissures 8 and 10.

Anchors 30 a and 30 b, ribbed crimping structures 34, and the distalends of surrounding sheaths 26 a and 26 b are advanced into ventricle 6.Subsequently, anchors 30 a and 30 b are pushed distally from withinsheaths 26 a and 26 b, (or sheaths 26 a and 26 b are pulled proximallywith respect to anchors 30 a and 30 b) to expose anchors 30 a and 30 b.As anchors 30 a and 30 b are exposed from within sheaths 26 a and 26 b,prongs 32 are free to expand, as shown in FIG. 1D. Prongs 32 expand suchthat anchors 30 a and 30 b assume a flower shape. Prongs 32,collectively in their expanded state, create a larger surface area toengage tissue than in their compressed states. Following the exposing ofanchors 30 a and 30 b, sheaths 26 a and 26 b are extracted.

As shown in FIG. 2B, lumens 27 a and 27 b are pulled proximally so thatprongs 32 of anchors 30 a and 30 b engage respective ventricular surfaceof commissures 8 and 10. Prongs 32 create a large surface area whichrestricts proximal motion of anchors 30 a and 30 b from commissures 8and 10, respectively.

For some applications, following the anchoring of anchors 30 a and 30 bto commissures 8 and 10, respectively, guide members 21 a and 21 b areremoved from the body of the patient.

Reference is now made to FIGS. 2C-F, which are schematic illustrationsof the advancement of a prosthetic valve support 40 along lumens 27 aand 27 b, in accordance with some applications of the present invention.In such a manner, lumens 27 a and 27 b function as valve support guidemembers. Support 40 comprises a collapsible skirt having a proximalannular element 44 and a distal cylindrical element 42. Support 40 isconfigured to assume a collapsed state (e.g., surrounded by a sheath orovertube 50 shown in FIG. 2C) for minimally-invasive delivery to thediseased native valve, such as by percutaneous or transluminal deliveryusing one or more catheters. FIG. 20 and the other figures show support40 in an expanded state after delivery in right atrium 4 and advancementtoward the native valve. As shown in FIG. 2D, support 40 is shaped so asto define one or more (e.g., two, as shown in View A) holes 46 a and 46b for slidable advancement of support 40 along lumens 27 a and 27 b,respectively. That is, prior to introduction of support 40 into the bodyof the patient, lumens 27 a and 27 b are threaded through holes 46 a and46 b, respectively, and support 40 is slid along lumens 27 a and 27 b.Support 40 is slid by pushing elements 52 a and 52 b which surrounddelivery lumens 27 a and 27 b, respectively.

It is to be noted that support 40 is slid along lumens 27 a and 27 b byway of illustration and not limitation. That is, for some applications,following the anchoring of anchors 30 a and 30 b to commissures 8 and10, respectively, guide members 21 a and 21 b are not removed from thebody of the patient, but rather lumens 27 a and 27 b are removed (e.g.,by being decoupled from crimping structures 34) leaving behind anchors30 a and 30 b and guide members 21 a and 21 b. Guide members 21 a and 21b may then be threaded through holes 46 a and 46 b, respectively, andsupport 40 is slid along guide members 21 a and 21 b. In such a manner,guide members 21 a and 21 b function as valve support guide members.

Support 40 comprises a collapsible flexible support frame 48, which isat least partially covered by a covering 49. Support 40 is configured tobe placed at native valve 5, such that cylindrical element 42 passesthrough the orifice of the native valve and extends towards, and,typically partially into, ventricle 6 (as shown in FIG. 2E). Cylindricalelement 42 typically pushes aside and presses against native leaflets ofnative valve 5 at least in part, which are left in place during andafter implantation of the prosthetic valve. Annular element 44 isconfigured to be placed around a native annulus 11 of the native valve,and to extend at least partially into an atrium 4 such that annularelement 44 rests against the native annulus. Annular element 44 istypically too large to pass through the annulus, and may, for example,have an outer diameter of between 30 and 60 mm.

For some applications, collapsible support frame 48 comprises a stent,which comprises a plurality of struts. The struts may comprise, forexample, a metal such as nitinol or stainless steel. For someapplications, frame comprises a flexible metal, e.g., nitinol, whichfacilitates compression of support 40 within a delivery sheath orovertube 50. For some applications, covering 49 comprises a fabric, suchas a woven fabric, e.g., Dacron. Covering 49 is typically configured tocover at least a portion of cylindrical element 42, and at least aportion of annular element 44. The covering may comprise a single piece,or a plurality of pieces sewn together.

As shown in FIG. 2D, pushing elements 52 a and 52 b are each coupled tolocking crimping elements 64 a and 64 b, respectively. Locking crimpingelements 64 a and 64 b are disposed adjacently, proximally to holes 46 aand 46 b respectively of valve support 40. These techniques enable thesurgeon to readily bring crimping elements 64 a and 64 b to theappropriate sites along annular element 44, without the need forexcessive imaging, such as fluoroscopy.

FIG. 2E shows valve support 40 prior to implantation at annulus 11. Asshown, ribbed crimping structures 34 project away from anchors 30 a and30 b, through commissures 8 and 10, and toward atrium 4. Valve support40 is advanced along lumens 27 a and 27 b toward structures 34 by beingpushed by pushing elements 52 a and 52 b and locking crimping elements64 a and 64 b.

In FIG. 2F, valve support 40 is further pushed by pushing elements 52 aand 52 b and locking crimping elements 64 a and 64 b such holes 46 a and46 b of support 40 advance around ribbed crimping structures 34. Asholes 46 a and 46 b are advanced around ribbed crimping structures 34,locking crimping elements 64 a and 64 b advance over and surround ribbedcrimping elements 34 to lock in place valve support 40 from an atrialsurface of valve 5.

Responsively to the placement of valve support 40 at native valve 5,cylindrical element 42 is positioned partially within ventricle 6 andnative leaflets 12 and 14 of native valve 5 are pushed aside.

As shown in section A-A, ribbed crimping structures 34 are shaped so asto define a plurality of male couplings. Locking crimping elements 64 aand 64 b each comprise a cylindrical element having an inner lumen thatis shaped so as to surround a respective ribbed crimping structure 34.Each inner lumen of locking crimping elements 64 a and 64 b is shaped soas to define female couplings to receive the male couplings of ribbedcrimping structure 34. The female couplings of locking crimping element64 are directioned such that they facilitate distal advancement oflocking crimping element 64 while restricting proximal advancement oflocking crimping element 64. When the female couplings of lockingcrimping element 64 receive the male couplings of ribbed crimpingstructure 34, valve support 40 is locked in place from an atrial surfaceof valve 5. It is to be noted that for some applications, ribbedcrimping elements 34 comprise female couplings, and locking crimpingelements 64 comprise male couplings.

Reference is now made to FIGS. 2G-K which are schematic illustrations ofthe coupling of a prosthetic atrioventricular valve 80 to valve support40, in accordance with some applications of the present invention.Support 40 receives the prosthetic valve and functions as a dockingstation. Thus, the docking station is a coupling element that providescoupling between two other elements (in this case, between annulus 11and the prosthetic valve.)

Following the placement of support 40 at annulus 11, pushing elements 52a and 52 b and sheath or overtube 50 are removed from the body of thepatient, leaving behind lumens 27 a and 27 b, as shown in FIG. 2G.

As shown in FIG. 2G, a guide wire 72 is advanced toward ventricle 6 andfacilitates the advancement of an overtube 70 through sheath 25 and thepositioning of a distal end of overtube 70 within ventricle 6. Overtube70 facilitates the advancement of prosthetic valve 80 in a compressedstate, toward valve support 40.

FIG. 2H shows partial deployment of valve 80 within ventricle 6 of heart2. Valve 80 is shown comprising a flexible wire frame comprising aplurality of stent struts by way of illustration and not limitation. Thewireframe of valve 80 comprises a flexible metal, e.g., nitinol orstainless steel. It is to be noted that the wireframe of valve 80 iscovered by a covering (not shown for clarity of illustration) comprisinga braided mesh or in a fabric such as a woven fabric, e.g., Dacron. Thecovering is typically configured to cover at least a portion of theframe. The covering may comprise a single piece, or a plurality ofpieces sewn together.

Following the partial deployment of valve 80 in ventricle 6, overtube 70is pulled proximally to pull valve 80 proximally such that cylindricalelement 42 of valve support 40 surrounds a proximal portion ofprosthetic valve 80. Valve 80 has a tendency to expand such that valve80 is held in place with respect to valve support 40 responsively toradial forces acted upon valve support 40 by prosthetic valve 80.

Valve 80 comprises a plurality of distal protrusions (e.g., snares).When valve 80 is pulled proximally, as described hereinabove,protrusions 84 ensnare and engage the native leaflets of theatrioventricular valve. By the ensnaring of the native leaflets,protrusions 84 sandwich the native valve between protrusions 84 andprosthetic valve support 40. Such ensnaring helps further anchorprosthetic valve 80 to the native atrioventricular valve. The scope ofthe present invention includes using any sort of protrusions (e.g.,hooks) that protrude from the distal end of the main frame of prostheticvalve 80 and that are configured such that the native valve issandwiched between the protrusions and valve support 40. Typically, theprotrusions cause sandwiching of the native valve leaflets, such thatthe leaflets do not interfere with the left ventricular outflow tract(LVOT).

For some applications, during the procedure, the prosthetic valve ispulled back proximally with respect to valve support, as describedhereinabove. The prosthetic valve is pulled back to a position withrespect to valve support that is such that protrusions 84 prevent thenative leaflets from interfering with the LVOT, by sandwiching thenative leaflets between the protrusions and the valve support. Theprosthetic valve is then deployed at this position.

For some applications, protrusions are disposed on the valve on thesides of the valve that are adjacent to the anterior and posteriorleaflets of the native valve, and the valve does not includesprotrusions on the portions of the valve that are adjacent to thecommissures of the native valve, as described with reference to FIGS.11A-D. For some applications, the protrusions are disposed in asinusoidal configuration in order to conform with the saddle shape ofthe native valve, as described hereinbelow with reference to FIGS.12A-C.

Additionally, as shown in FIG. 2J, valve 80 comprises one or more (e.g.,a plurality, as shown) coupling elements 81 at the proximal end of valve80. Overtube 70, which facilitates the advancement of prosthetic valve80, is reversibly coupled to valve 80, via coupling elements 81.

Prosthetic valve 80 is configured for implantation in and/or at leastpartial replacement of a native atrioventricular valve 5 of the patient,such as a native mitral valve or a native tricuspid valve. Prostheticvalve 80 is configured to assume a collapsed state forminimally-invasive delivery to the diseased native valve, such as bypercutaneous or transluminal delivery using one or more catheters. FIG.2J shows prosthetic valve 80 in an expanded state after delivery to thenative valve.

Reference is now made to FIG. 2K which shows a bird's-eye view of valve80. Prosthetic valve 80 further comprises a plurality of valve leaflets82, which may be artificial or tissue-based. The leaflets are typicallycoupled to an inner surface of the valve prosthesis. Leaflets 82 arecoupled, e.g., sewn, to the frame and/or to the covering. Forapplications in which the prosthetic valve is configured to be implantedat the native mitral valve, the prosthetic valve typically comprisesthree leaflets 82 a, 82 b, and 82 c, as shown in FIG. 2K.

Reference is now made to FIGS. 3A-D, which are schematic illustrationsof the advancement of prosthetic valve support 40 toward nativeatrioventricular valve 5 of a patient, the valve support including asealing balloon 90, in accordance with some applications of the presentinvention. The steps shown in FIGS. 3A-C are generally similar to thoseshown in FIGS. 2C-F. For some applications, sealing balloon 40 isdisposed on the valve-facing, lower side of annular element 44 of theprosthetic valve support. FIG. 3D shows valve support 40, the valvesupport having been implanted at annulus 11. Typically, at this stage,balloon 40 is inflated, as shown in the transition from FIG. 3C to FIG.3D. The balloon is inflated via an inflation lumen 92, shown in FIG. 3C,for example. For some applications, the balloon seals the interfacebetween the prosthetic valve support and native annulus 11, therebyreducing retrograde blood flow from ventricle 6 into atrium 4, relativeto retrograde blood flow in the absence of a sealing balloon. For someapplications, the balloon is inflated prior to the placement of theprosthetic support at annulus 11.

Reference is now made to FIGS. 4A-C, which are schematic illustrationsof prosthetic valve support 40 being used with commissural helices 100 aand 100 b that facilitate anchoring and/or sealing of the valve support,in accordance with some applications of the present invention. For someapplications, commissural helices are used as an alternative or inaddition to anchors 30 a and 30 b and/or other anchoring elementsdescribed herein, in order to facilitate the anchoring of valve support40.

Commissural helices 100 a and 100 b are typically placed at commissures8 and 10 in a generally similar technique to that described withreference to anchors 30 a and 30 b. Typically, each helix 30 a and 30 bis reversibly coupled to a respective delivery lumen 27 a and 27 b. Asdescribed above, each delivery lumen 27 slides around a respective guidemember 21, and a respective surrounding sheath 26 a and 26 b surroundseach delivery lumen 27 a and 27 b.

Commissural helices 100 a and 100 b (optionally, ribbed crimpingstructures 34), and the distal ends of surrounding sheaths 26 a and 26 bare advanced into ventricle 6. The helices are pushed out of the distalends of surrounding sheaths 26 a and 26 b. Subsequently, the helices arerotated proximally such that the helices wrap around at least somechordae tendineae 102 of the patient. Following the advancement of thehelices out of sheaths 26 a and 26 b, the sheaths are extracted. Forsome applications the helices are conical helices (as shown), and thewider end of the conical helix is disposed at the proximal end of thehelix.

Subsequent to the placement of commissural helices 100 a and 100 baround the chordae tendineae, prosthetic valve support 40 is placed atannulus 11, in accordance with the techniques described hereinabove, andas shown in FIG. 4B. Subsequently, prosthetic valve 80 is coupled to theprosthetic valve support, in accordance with the techniques describedhereinabove, and as shown in FIG. 4C.

Typically, commissural helices 100 a and 100 b facilitate sealing ofnative commissures 8 and 10, thereby reducing retrograde blood flow viathe commissures, relative to retrograde blood flow in the absence of thehelices. Further typically, the sealing of the native commissuresfacilitates anchoring of the prosthetic valve support to native valve 5.

Reference is now made to FIGS. 5A-D, which are schematic illustrationsof grasping elements 106 a and 106 b being used to anchor prostheticvalve 80, in accordance with some applications of the present invention.For some applications, guide members 21 a and 21 b are advanced towardfirst and second commissures 8 and 10 of valve 5 of the patient, asdescribed hereinabove. Grasping elements 106 a and 106 b are reversiblycoupled to distal ends of delivery lumen 27 a and 27 b, the deliverylumens being advanced over respective guide members, as describedhereinabove. For some applications, the guiding members and the graspingelements are advanced toward the patient's commissures via surroundingsheaths 26 a and 26 b, the surrounding sheaths being generally asdescribed hereinabove. The grasping elements are typically placeddistally to the commissures in a proximally-facing configuration, asshown in FIG. 5A. For example, as shown, the grasping elements may beconfigured to be proximally facing due to the coupling of the graspingelements to the guide members.

Subsequent to the placement of grasping elements 106 a and 106 bdistally to native commissures 8 and 10, prosthetic valve 80 is advancedtoward native valve 5, as shown in FIG. 5B. For example, the prostheticvalve may be advanced over delivery lumens 27 a and 27 b, as shown. Theprosthetic valve is placed at the native valve and, subsequently, thegrasping elements are retracted proximally toward commissures 8 and 10,as shown in the transition from FIG. 5B to FIG. 5C. For someapplications, the grasping elements are coupled to valve 80 via couplingtubes 107 a and 107 b, the coupling tubes being coupled to the sides ofthe valve, as shown. The grasping elements are closed such that thenative commissures are grasped and sealed by the grasping elements, asshown in FIG. 5D. Typically, the grasping elements define two surfacesthat are hingedly coupled to each other. For example, the graspingelements may include forceps, as shown. The grasping elements are closedby closing the surfaces about the hinge, with respect to one another.

Typically, grasping elements 106 a and 106 b facilitate sealing ofnative commissures 8 and 10, thereby reducing retrograde blood flow viathe commissures, relative to retrograde blood flow in the absence of thegrasping elements. Further typically, the sealing of the nativecommissures facilitates anchoring of the prosthetic valve to nativevalve 5.

Although not shown, for some applications, prosthetic valve support 40is used in addition to grasping elements 106 a and 106 b, in order toanchor prosthetic valve 80 to native valve 5. For some applications, thegrasping elements are used to anchor and/or provide sealing forprosthetic valve support 40 (instead of, or in addition to, being usedto anchor prosthetic valve 80, as shown). For such applications,generally similar techniques are used to those described with respect tothe use of the grasping elements for anchoring the prosthetic valve,mutatis mutandis.

Reference is now made to FIGS. 6A-B, which are schematic illustrationsof prosthetic valve 80, the prosthetic valve comprising a sealingmaterial 110 on an outer surface of the valve, in accordance with someapplications of the present invention. For some applications, prostheticvalve 80 is used in conjunction with prosthetic valve support 40, asdescribed hereinabove. The techniques for implanting prosthetic valve 80as shown in FIGS. 6A-B are generally similar to those describedhereinabove. Typically, sealing material 110 seals the interface betweenthe prosthetic valve and native valve 5. The sealing material reducesretrograde blood flow from ventricle 6 into atrium 4, relative toretrograde blood flow in the absence of the sealing material. Typically,the sealing material is composed of latex, dacron, and/or any othersuitable biocompatible material. The sealing material is typicallyplaced around at least a portion of the wire frame of the prostheticvalve so as to form a webbing between struts of the wire frame.

Reference is now made to FIGS. 7A-F, which are schematic illustrationsof a guide wire delivery system, in accordance with some applications ofthe present invention. As described hereinabove (e.g., with reference toFIGS. 2C-F), for some applications, guide members 21 a and 21 b,function as valve support guide members, by support 40 being slid alongguide members 21 a and 21 b. For some applications, only one guidemember 21 is looped through commissures 8 and 10 in a manner in whichthe guide member defines a looped portion between commissures 8 and 10(i.e., a portion of the guide member that is disposed in a ventricle 6of heart 2), and first and second free ends, which are disposed andaccessible at a site outside the body of the patient. For suchapplications, the guide member defines portions 21 a and 21 b.

For some applications, an anchor 302 is advanced toward the vicinity ofapex 304 of heart 2, via sheath 25, and is anchored to the vicinity ofthe apex, as shown in FIG. 7A. A guidewire 306 extends proximally fromanchor. Guide member 21 passes through a guide member tube 320, theguide member tube being coupled to guidewire 306. Guide member 21 ispushed distally. Guide member tube 320 is unable to advance distallyover guidewire 306, due to the coupling of the guide member tube to theguidewire. Therefore, the pushing of guide member 21 distally, causesportions 21 a and 21 b to spread apart from one another and to be pushedagainst commissures 8 and 10 of native valve 5. Portions 21 a and 21 bare then used to guide valve support 40 to the commissures, as shown inFIGS. 7B-F, using generally similar techniques to those describedhereinabove, except for the differences described hereinbelow.

As shown in FIG. 7B, valve support 40 is slid over guide member portions21 a and 21 b, by pushing elements 52 a and 52 b. Since the guide memberportions are positioned at commissures 8 and 10, the guide memberportions guide the distal ends of pushing elements 52 a and 52 b, suchthat the pushing elements push the valve support against thecommissures, as shown in FIG. 7C.

Subsequent to the placement of valve support 40 at the native valve,prosthetic atrioventricular valve 80 is coupled to valve support 40. Forsome applications, pushing elements 52 a and 52 b continue to push thevalve support against the native valve, during the coupling of theprosthetic valve to the valve support. As described hereinabove,overtube 70 is advanced into ventricle 6, as shown in FIG. 7D. FIG. 7Eshows prosthetic valve having been partially deployed in the ventricle.Following the partial deployment of valve 80 in ventricle 6, overtube 70is pulled proximally to pull valve 80 proximally such that cylindricalelement 42 of valve support 40 surrounds a proximal portion ofprosthetic valve 80. Valve 80 has a tendency to expand such that valve80 is held in place with respect to valve support 40 responsively toradial forces acted upon valve support 40 by prosthetic valve 80. Duringthe pulling back of overtube 70, pushing elements 52 a and 52 b pushvalve support 40 against the valve, thereby providing a counter forceagainst which overtube 70 is pulled back. For some applications, thepushing of the valve support against the commissures is such that it isnot necessary to use anchors for anchoring the valve support to thenative valve during the coupling of the prosthetic valve to the valvesupport. Alternatively, in addition to the pushing elements providing acounter force against which the prosthetic valve is pulled, anchors areused to anchor the valve support to the native valve during the couplingof the prosthetic valve to the valve support.

As described hereinabove, valve 80 comprises a plurality of distalprotrusions 84. When valve 80 is pulled proximally, as describedhereinabove, protrusions 84 ensnare and engage the native leaflets ofthe atrioventricular valve. By the ensnaring of the native leaflets,protrusions 84 sandwich the native valve between protrusions 84 andprosthetic valve support 40. Such ensnaring helps further anchorprosthetic valve 80 to the native atrioventricular valve.

Subsequent to the placement of the prosthetic valve at the native valve,sheath 25, overtube 70, pushing elements 52 a and 52 b, guide member 21,anchor 302, and guidewire 306 are removed from the patient's body, asshown in FIG. 7F, which shows the prosthetic valve in its deployedstate. For some applications, in order to remove guide member 21 fromthe patient's body, guide member portions 21 a and 21 b are decoupledfrom guide member tube 320. For example, the guide member portions maybe coupled to the guide member tube via threading, the guide memberportions being decoupled from the guide member tube by unscrewing theguide member portions from the guide member tube.

Reference is now made to FIGS. 8A-C which are schematic illustrations ofa system 120 comprising an invertible valve support 140, in accordancewith some applications of the present invention. Invertible valvesupport 140 is identical to valve support 40 described herein, with theexception that the cylindrical element of valve support 140 isinvertible, as is described hereinbelow. Additionally, the method ofadvancing toward and implanting valve support 140 at annulus 11 isidentical to the methods of advancing toward and implanting valvesupport 40 at annulus 11, as described hereinabove.

Valve support 140 comprises an annular element 144 (that is identical toannular element 44 described hereinabove) and a cylindrical element 142.Cylindrical element 142 has a first end 150, a second end 152, and acylindrical body 153 disposed between first and second ends 150 and 152.Cylindrical element 142 is attached to annular element 144 at first end150 of cylindrical element 142.

During and following implantation of support 140 at annulus 11, as shownin FIG. 8A, cylindrical element 142 is disposed above annular element144 in a manner in which second end 152 and cylindrical body 153 aredisposed above annular element 144 and within atrium 4. One or moreelongate guide members 146 a and 146 b are reversibly coupled tocylindrical element 142 in a vicinity of second end 152. Elongate guidemembers 146 a and 146 b facilitate (a) advancement of prosthetic valve80 therealong and toward valve support 140, and (b) inversion ofcylindrical element 142 toward ventricle 6 when at least a portion ofvalve 80 is deployed within ventricle 6 (as shown in FIG. 8B).

The configuration of valve support 140 as shown in FIG. 8A (i.e., theconfiguration in which cylindrical element 142 is disposed within atrium4) eliminates the obstruction of native valve 5 and of leaflets 12 and14 by any portion of valve support 140. In this manner, valve support140 may be implanted at valve 5 while valve 5 resumes its nativefunction and leaflets 12 and 14 resume their natural function (as shownby the phantom drawing of leaflets 12 and 14 in FIG. 8A which indicatestheir movement). This atrially-inverted configuration of valve support140 reduces and even eliminates the amount of time the patient is undercardiopulmonary bypass. Only once prosthetic valve 80 is delivered andcoupled to valve support 140 and cylindrical element 142 is therebyventricularly-inverted, native leaflets 12 and 14 are pushed aside (FIG.8B).

FIG. 8B shows the inversion of cylindrical element 142 by the partialpositioning and deployment of prosthetic valve 80 within ventricle 6.Elongate guide members 146 a and 146 b are reversibly coupled toprosthetic valve 80 and extend within overtube 70. Following the fulldeployment of valve 80 and the coupling of valve 80 to valve support140, elongate guide members 146 a and 146 b are decoupled fromprosthetic valve 80 and from cylindrical element 142. For example, acutting tool may be used to decouple elongate members 146 a and 146 bfrom the valve support 140. Alternatively, elongate members 146 a and146 b may be looped through the cylindrical element 142, such that bothends of each elongate member 146 a and 146 b remain outside of thepatient's body. The operating physician decouples elongate members 146 aand 146 b from valve support 140 by releasing one end of each ofelongate members 146 a and 146 b and pulling on the other end, untilelongate members 146 a and 146 b are drawn from valve support 140 andremoved from within the body of the patient.

FIG. 8C shows prosthetic valve 80 coupled to valve support 140. Valve 80is identical to the valve described hereinabove.

Reference is now made to FIGS. 9A-E, which are schematic illustrationsof the advancement of an invertible prosthetic valve support 300 towarda native atrioventricular valve of a patient, and inversion of the valvesupport, in accordance with some applications of the present invention.Prosthetic valve support 300 is used to anchor prosthetic valve 80 tonative valve 5 in a generally similar manner to that described withreference to prosthetic valve support 40.

During a typical procedure, anchor 302 is advanced toward the vicinityof apex 304 of heart 2, via sheath 25, and is anchored to the vicinityof the apex, as shown in FIG. 8A. A guidewire 306 extends proximallyfrom anchor. A distal tensioning element 308 (e.g., a plunger) isadvanced over guidewire 306 into ventricle 6, and prosthetic valvesupport 300 is advanced out of the distal end of sheath 25, as shown inFIG. 9B. A first end 310 of prosthetic valve support 300 (which at thisstage is the distal end of the prosthetic valve support), comprisesbarbs 314 (shown in FIG. 9B), or other anchoring elements for anchoringthe first end of the prosthetic valve support to tissue of native valve5. Prosthetic valve support 300 is pushed distally such that the barbsare pushed into the native valve tissue, thereby anchoring the first endof the prosthetic valve support to the native valve, as shown in FIG.9C. A plurality of wires 309 pass from distal tensioning element 308 toa proximal tensioning element 311 (shown in FIG. 9D), via a second end312 of valve support 300 (which at this stage is the proximal end of theprosthetic valve support). For some applications, a sealing element 316is disposed circumferentially around a surface of the invertibleprosthetic valve support that is initially an inner surface of theinvertible prosthetic valve support (a shown in FIGS. 8A-D). Forexample, the sealing material may be latex, dacron, or another suitablebiocompatible sealing material.

Subsequent to the anchoring of first end 310 of prosthetic valve support300 to native valve tissue (as shown in FIG. 9C), distal tensioningelement 308 is further advanced distally into ventricle 6, and proximaltensioning element 311 is advanced toward the ventricle. As shown in thetransition from FIG. 9D-F, as the proximal tensioning element passesthrough the valve support, wires 309 cause valve support 300 to invert,by pulling second end 312 of the valve support through first end 310 ofthe valve support. Subsequent to the inversion of the valve support,sealing material 316 is disposed circumferentially around the outside ofthe valve support, thereby providing a seal at the interface betweenvalve support 300 and native valve 5.

Reference is now made to FIGS. 9G-H, which are schematic illustrationsof the deployment of prosthetic valve 80 and the coupling of theprosthetic valve to invertible valve support 300, in accordance withsome applications of the present invention.

The deployment of prosthetic valve 80 is generally similar to thetechniques described hereinabove with reference to FIGS. 2H-J. The valveis partially deployed in ventricle 6, via overtube 70. Following thepartial deployment of valve 80 in ventricle 6, overtube 70 is pulledproximally (as shown in FIG. 8G) to pull valve 80 proximally such thatvalve support 300 surrounds a proximal portion of prosthetic valve 80,as shown in FIG. 8H. Valve 80 has a tendency to expand such that valve80 is held in place with respect to valve support 300 responsively toradial forces acted upon valve support 300 by prosthetic valve 80.

As described hereinabove, for some applications, valve 80 comprises aplurality of distal protrusions 84. When valve 80 is pulled proximally,protrusions 84 ensnare and engage the native leaflets of theatrioventricular valve. By the ensnaring of the native leaflets,protrusions 84 sandwich the native valve between protrusions 84 andprosthetic valve support 300. Such ensnaring helps further anchorprosthetic valve 80 to the native atrioventricular valve.

Additionally, as shown in FIG. 9H, and as described hereinabove, valve80 comprises one or more (e.g., a plurality, as shown) coupling elements81 at the proximal end of valve 80. Overtube 70, which facilitates theadvancement of prosthetic valve 80, is reversibly coupled to valve 80,via coupling elements 81.

Subsequent to the coupling of valve 80 to valve support 300, overtube70, distal and proximal tensioning elements 308 and 311, and wires 309are removed from the patient's body, via sheath 25. Typically, wires 309are cut, in order to facilitate the removal of the wires from thepatient's body. Guidewire 306 and anchor 302 are removed from thepatient's body by detaching the anchor from apex 304, and withdrawingthe anchor and the guidewire, via sheath 25.

Reference is now made to FIG. 10, which is a schematic illustration ofprosthetic valve 80, for placing inside atrioventricular valve 5 of thepatient, in accordance with some applications of the present invention.The frame of the prosthetic valve has a diameter d, and a correspondingcross-sectional area. Native annulus 11, which is typicallysaddle-shaped, defines an area A, as shown. For some applications, areaA, which is defined by the native annulus is measured, e.g., using ameasuring ring. A prosthetic valve is chosen to be placed in theannulus, the cross-sectional area of the prosthetic valve being lessthan 90% (e.g., less than 80%, or less than 60%) of area A. For someapplications, placing a prosthetic valve inside the native valve withthe dimensions of the native valve annulus and the prosthetic valve asdescribed, facilitates sealing of the prosthetic valve with respect tothe native valve, by the native valve leaflets closing around the outersurface of the prosthetic valve.

For some applications, in order to facilitate the sealing of the nativevalve around the outer surface of the prosthetic valve, a material isplaced on the outer surface of the prosthetic valve in order to providea sealing interface between the prosthetic valve and the native valve.For example, a smooth material that prevents tissue growth (e.g.,polytetrafluoroethylene (PTFE), and/or pericardium) may be placed on theouter surface of the prosthetic valve. Alternatively or additionally, amaterial that facilitates tissue growth (such as dacron) may be placedon the outer surface of the prosthetic valve, in order to (a) act as asealing interface between the native valve and the prosthetic valve, and(b) facilitate tissue growth around the prosthetic valve to facilitateanchoring and/or sealing of the prosthetic valve.

Reference is now made to FIGS. 11A-D, which are schematic illustrationsof prosthetic valve 80, in accordance with some applications of thepresent invention. For some applications, protrusions 84 are disposed onthe valve on portions 400 of the valve that are placed adjacent to theanterior and posterior leaflets of the native valve, and the valve doesnot includes protrusions on portions 402 of the valve that are placedadjacent to the commissures of the native valve.

FIGS. 11B-D show bottom views (i.e., views of the distal ends) ofrespective configurations of prosthetic valve 80 and protrusions 84. Theprotrusions converge from the proximal ends 404 of the protrusion to thedistal ends 406 of the protrusions. The protrusions are configured suchas to ensnare chordae tendineae, and to pull the chordae tendineaetoward each other when the prosthetic valve is pulled proximally, due tothe convergence of the snares with respect to each other. FIG. 11D showsthe prosthetic valve deployed at native valve 5. As shown, theprotrusions ensnare chordae tendineae 102 of the patient. Theprotrusions facilitate sealing and anchoring of the prosthetic valvewith respect to the native valve by pulling the chordae tendinae towardeach other, as described. As described hereinabove, for someapplications the prosthetic valve does not define protrusions 84 onportions 402 that are placed next to the native commissures, e.g.,commissure 8, shown in FIG. 11D.

For some applications, a first set of protrusions 84 from the distal endof prosthetic valve 80 are disposed the within a first circumferentialarc with respect to a longitudinal axis of the prosthetic valve, on afirst side of the distal end of the prosthetic valve, the first side ofthe distal end being configured to be placed adjacent to the anteriorleaflet of the native valve. A second set of protrusions are disposedthe within a second circumferential arc with respect to a longitudinalaxis of the prosthetic valve, on a second side of the distal end of theprosthetic valve, the second side of the distal end being configured tobe placed adjacent to the posterior leaflet of the native valve.

The first and second sets of protrusions are disposed so as to providefirst and second gaps therebetween at the distal end of the prostheticvalve. Typically, at least one of the gaps between the two sets ofprotrusions has a circumferential arc of at least 20 degrees (e.g., atleast 60 degrees, or at least 100 degrees), and/or less than 180 degrees(e.g., less than 140 degrees), e.g., 60-180 degrees, or 100-140 degrees.Further typically, one or both of the first and second circumferentialarcs defines an angle of at least 25 degrees (e.g., at least 45degrees), and/or less than 90 degrees (e.g., less than 75 degrees),e.g., 25-90 degrees, or 45-75 degrees.

Valve guide members (e.g., guide members 21 a and 21 b, and/or deliverylumen 27 a and 27 b, as described hereinabove) are delivered tocommissures of the native valve, and guide the valve such that the firstand second circumferential arc are aligned with respective leaflets ofthe native valve and such that the first and second gaps are alignedwith respective commissures of the native valve.

Reference is now made to FIGS. 12A-C, which are schematic illustrationsof prosthetic valve 80, the valve defining distal protrusions 84 thatare disposed sinusoidally around the circumference of the valve, inaccordance with some applications of the present invention. For someapplications the protrusions are shaped sinusoidally, in order toconform with the saddle-shape of native valve annulus 11, therebyfacilitating the sandwiching of the native valve leaflets between theprotrusions and valve support 40. As shown, the peaks of the sinusoidthat is defined by the protrusions is disposed on portions 402 that areplaced next to the native commissures and the troughs of the sinusoid isplaced on portions of the valve that are placed in the vicinity of thecenters of the anterior and posterior leaflets of the native valve. Asshown in FIG. 12C, for some applications the distal end of theprosthetic valve defines a sinusoidal shape.

Reference is now made to FIGS. 1A-D, 2A-K, 3A-D, 4A-C, 5A-D, 6A-B, 7A-F,8A-C, 9A-H, 10, 11A-D, and 12A-C. It is to be noted that valve support40 may be invertible as described hereinabove with respect to valvesupports 140 and 300, with reference to FIGS. 8A-C, and 9A-H. It is tobe further noted that valve supports 140 and 300 may be used inconjunction with one or more of the elements for facilitating sealing ofthe native valve with respect to a valve support or a valve that isdescribed with reference to FIGS. 3A-D, 4A-C, 5A-D, and 6A-B. Forexample, valve supports 140 and 300 may be used with sealing balloon 90,commissural anchors 100 a and 100 b, grasping elements 106 a and 106 b,and/or sealing material 110. It is still further noted that valvesupports 140 and 300 may be implanted using a guide member that definesa looped portion between commissures 8 and 10, as described withreference to FIGS. 7A-F. It is further noted that any of theapplications described herein can be used in conjunction with valveshaving configurations as described with reference to FIGS. 10-12C.

The systems described herein are advanced toward valve in atranscatheter procedure, as shown. It is to be noted, however, that thesystems described herein may be advanced using any suitable procedure,e.g., minimally-invasive or open-heart. It is to be further noted thatvalve supports and prosthetic valves herein may be used to replacenative mitral valves or native tricuspid valves.

It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed hereinabove. Rather, the scope of the present inventionincludes both combinations and subcombinations of the various featuresdescribed hereinabove, as well as variations and modifications thereofthat are not in the prior art, which would occur to persons skilled inthe art upon reading the foregoing description.

The invention claimed is:
 1. A method, comprising: placing an annularelement of a prosthetic valve support against an annulus of a nativeatrioventricular valve of a patient; subsequently, delivering aprosthetic valve, having a main frame and one or more snares coupled tothe main frame, to the native atrioventricular valve; and deploying theprosthetic valve at the native valve, the step of deploying comprising:ensnaring at least one leaflet of the native valve with the one or moresnares, and expanding the prosthetic valve such that an outer surface ofthe main frame of the prosthetic valve defines a cross-sectional areathat is not more than 90% of an area defined by an annulus of the nativeatrioventricular valve.
 2. The method according to claim 1, furthercomprising: determining the area defined by the annulus of the nativeatrioventricular valve of the patient; and selecting the prostheticvalve by determining that the outer surface of the main frame of theprosthetic valve defines the cross-sectional area that is not more than90% of the area defined by the annulus, the selecting of the prostheticvalve facilitating sealing of the native valve with respect to theprosthetic valve by facilitating closing of leaflets of the native valvearound the prosthetic valve, upon deployment of the prosthetic valve. 3.The method according to claim 2, wherein selecting the prosthetic valvecomprises selecting a prosthetic valve having a material disposed on anouter surface thereof.
 4. The method according to claim 3, whereinselecting the prosthetic valve comprises selecting a prosthetic valvehaving a material that prevents tissue growth disposed on an outersurface thereof.
 5. The method according to claim 3, wherein selectingthe prosthetic valve comprises selecting a prosthetic valve having amaterial that promotes tissue growth disposed on an outer surfacethereof.
 6. The method according to claim 1, wherein expanding theprosthetic valve comprises expanding the prosthetic valve such that theouter surface of the main frame of the prosthetic valve defines across-sectional area that is less than 80% of the area defined by theannulus.
 7. The method according to claim 6, wherein expanding theprosthetic valve comprises expanding the prosthetic valve such that theouter surface of the main frame of the prosthetic valve defines across-sectional area that is less than 60% of the area defined by theannulus.
 8. The method according to claim 2, wherein deploying theprosthetic valve comprises deploying at least a portion of theprosthetic valve within the prosthetic valve support.
 9. The methodaccording to claim 8, wherein deploying the at least the portion of theprosthetic valve within the prosthetic valve support comprises expandingthe at least the portion of the prosthetic valve such that the at leastthe portion of the prosthetic valve applies a radial force to theprosthetic valve support.
 10. The method according to claim 1, whereinthe one or more snares are coupled to a downstream portion of the mainframe, and wherein delivering the prosthetic valve comprises deliveringthe prosthetic valve having the one or more snares coupled to thedownstream portion of the main frame.
 11. The method according to claim1, wherein deploying the prosthetic valve comprises expanding at least aportion of the prosthetic valve within the prosthetic valve support. 12.The method according to claim 1, wherein placing the annular elementagainst the annulus comprises pushing the annular element against theannulus using a percutaneously-advanceable pushing element, and whereinthe method further comprises: after placing the annular element againstthe annulus, and during the deployment of the prosthetic valve, holdingthe annular element against the annulus by continuing to push theannular element against the annulus using the pushing element; andsubsequently, removing the pushing element from the annular element.